The upper part of the respiratory system includes the ears, nose, sinuses, mouth, and throat. It also includes the main bronchi or windpipes, which are the air-carrying tubes in the chest. The upper respiratory system is the most commonly infected area in the body.
The term upper respiratory infection (URI) includes the common cold, sore throats, and flu. URIs are usually caused by a virus but may also be due to bacteria or other organisms. An upper respiratory infection is rarely serious but often causes bothersome symptoms.
There are many different types of upper respiratory infections, including:
Other types of URI may also occur, but they are less common.
Many of the signs and symptoms depend on the type of upper respiratory infection. Common symptoms of URIs include:
The healthcare provider diagnoses most URIs after a history and physical exam.
In some cases, further tests may be ordered. For example, the back of the throat may be swabbed if strep throat is suspected. This swab test, called a throat culture, can check for the bacteria that cause this infection. A blood test called an antibody titer may be done if certain infections are suspected. A chest X-ray may be ordered to make sure pneumonia, a more serious infection deep in the lungs, is not present. Other tests may be ordered in certain cases.
Many cases of upper respiratory infection cannot be prevented. Almost all URIs are contagious, so avoiding sick people can help prevent some cases. Frequent hand washing can also help reduce the spread of many URIs. Vaccines are used to help prevent some cases. For example, the flu shot can be given to high-risk individuals every fall to help prevent the flu.
Most URIs are mild and go away with or without treatment. However, some URIs can be more serious and may have long-term effects. For example, untreated strep throat can lead to kidney damage or rheumatic fever, which can damage the heart. Acute otitis media can result in hearing loss. Severe croup and epiglottitis may be life-threatening. URIs can also put people at risk of getting pneumonia, which may be life-threatening, especially in the elderly and very young.
Most upper respiratory infections are highly contagious. They are transmitted through respiratory secretions. Sneezing and coughing can spread these droplets. The germ can also be passed on when an individual with an upper respiratory infection touches his or her nose and then handles an object that another person later touches. The second person can then pick up the germ from the object and transfer it into his or her own respiratory tract by touching the face.
For URIs caused by a virus, antibiotics are not helpful. Someone with a cold should remember that antibiotics can cause more harm than good in these cases. In severe cases of the flu, antiviral medications such as rimantadine or oseltamivir may be given. For bacterial infections such as bacterial pneumonia, antibiotics are given.
Other treatments may help relieve symptoms. Other over-the-counter and prescription medications can be used for symptoms such as cough, fever, muscle aches, runny nose, or stuffy nose.
A decongestant called phenylpropanolamine (PPA), found in many over-the-counter cold remedies, has recently been linked to strokes in young women. The Food and Drug Administation (FDA) has requested that manufacturers stop producing medications containing PPA. In view of the FDA's public health advisory, anyone who has products at home containing phenylpropanolamine should discard them.
All medications have possible side effects. Common antibiotics can cause allergic reactions, stomach upset, and other effects.
Most people recover completely within a few days. Having a URI usually doesn't prevent a person from catching another URI in the future. If long-term effects such as kidney damage occur from the URI, a person may need further treatment.
If symptoms continue to get worse or fail to improve after several days, the healthcare provider should be told. In severe cases, a person may need to be watched in the hospital for a few days.
Author:Adam Brochert, MD
Editor:Ballenberg, Sally, BS
Reviewer:Eileen McLaughlin, RN, BSN
Harrison's Principles of Internal Medicine, 1998, Fauci et al.
Rudolph's Fundamentals of Pediatrics, 1998, Rudolph et al.